Floor sander



Dec. 10, 1940. T. E. LA SALLE FLOOR SANDER Filed Dec. 51, 19 38 2 Sheets-Sheet l INVENTOR I T E. LaSaMe BY QM .m 3&7;

ATTORNEY D88. 10, T E LA S LLE FLOOR SANDER Filed Dec. 31, 1938 2 Sheets-Sheet 2 a WI/I/MI/I/II/II/ INVENTOR TELaSa Le ATTORNEY Patented Dec. 10, 1940 UNITED STATES FLOOR SANDER v Thomas Edward La Salle, Merced, Calif.

Applicationnecember 31, 1933, Serial No. 248,713

3 Claims.

This invention relates generally to a sanding machine, and in particular the invention is directed to an improved power driven floor sander of the type used for finishing hardwood floors and the like.

The principal object of the invention is to provide a power driven floor sander which includes structure, controlled by a manually actuated member, arranged to facilitate movement of the sanding drum to and from anoper'ativ'e or floor engaging position; such structure being relatively simple and incorporating adjustable means whereby the pressure of the drum on the floor -may be varied to the desired degree.

Another object of the invention is to provide, in a power .driven floor sander which includes a relatively heavy electric motor, a means to mount the motor in such position that the sander as a whole has a very low center of gravity and so that the weight of the motor does not inter-. few with the extremely sensitive and easy. operation of the sander, whichI am able to obtain.

A further object of the invention is to include,

with one of the supporting wheel mounts, means for adjusting such wheel in a vertical plane, whereby proper horizontal alinement andcontact of the sanding drum and floor can be obtained.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings similar characters of refernce indicate corresponding parts in the several 1 views:

Figure 1 is a side elevation of the device illustrating the same in operative position.

Figure'a is a side elevation, partly in section, of the device illustrating the same in inoperative position.

Figure 3 is a top plan view of the supporting truck and yoke assembly.

Figure 4 "is a vertical section of one of the supporting wheels and the adjustment means therefor.

Referring now more particularly to the characters of reference on the drawings, the device comprises a pair of vertical, transversely spaced side plates 1 secured in fixed relation by means of a top plate 2*; said top plate sloping forward and downward from its rear edge .as shown and for the purpose hereinafter set forth. The side platesl are of course cut down at their upper edges to the plane of the top plate, and such top plate terminates short of the forward end of the side plates. The side plates and top plate form, in effect, a housing and frame .unit. The forward ends of thelside plates and beyond the top plate increase in height, aslat 3, and form .a portion of the end walls for a hood 4 which .encloses a relatively large, transversely extending sanding drum 5, journaled between 10 said side plates, in the conventional manner; the front, portion ,6 .of the hood being hinged as at l for upward'swinging movement, .and whereby to provideraccess to drum '5 for the purpose of placing or removingthe sandingsleeve thereon.

A heavy duty but highspeed electric .motor 8 is mounted on the sloping top plate 2 as far forward as possible, and with its shaft 9 extending transversely. A multiple groove pulley unit Hi is fixed on shaft 9 and an endless belt ll 20 engages about said pulley in one groove and extends down to" driving engagement with another pulley !2 mounted on the end of and axially with the sanding drum outwardly of the adjacent side plate .I. from the .drum is drawn into a duct [3 by means ofasuetion fan unit [4 which includes .an outlet tube 15 adapted for connection with a receivin bag (not shown); means of a belt 16 which extends from another groove in pulley unit. ill about .a pulley l! on the fan shaftr A forwardly open yoke i8 is disposed between the side plates I under the top plate 2 and immediatelyrearward of the sanding drum; such 35 yoke straddling the duct l3 .as shown in Fig. .2. Adjacent their free end, the yoke arms [9 turn on laterally and outwardly .proj ecting stub shafts 25 which extends through and are mounted in connection with the side plates in .fixed non- 40 rotatable relation. Asshown in Fig.4, one of the shafts is mounted for vertical adjustment; the mounting means including a collar 2| fixed on the outer endportion of the shaft and engaged by an adjustment screw 22 supplied by 45 the adjacent side plate, said plate having a vertical slot as shown through which the adjacent portion of the shaft projects. p

' Between the yoke arms l9 and side plates I, the shafts 2! support wheels 23 which are of sufiicien t diameter to extend below the side plates for engagement with the floor. These" wheels are ball bearing mounted in order to' providev ease of movement of the sander, and each'wheel includes an integral rim 24 on which 55 As is usual, wood dust 2:5

The fan unit I4 is driven by is vulcanized a rubber tire 25. The tires are preferably of red or white rubber, as black rubber tends to stain a floor as the machine is in operation and moves back and forth.

The yoke I8 is formed with a rigid, rearwardly extending bar 26 which projects beneath the top plate to a termination some distance therebeyond; the rear end of such bar being supported by a caster wheel unit 21 and which unit includes a wheel 28 constructed in the same manner as wheels 23.

A rigid post 29 is fixed on bar 26 intermediate its ends and is disposed at an upward and rearward slope whereby to clear the rear edge of top plate I; the upper end of such post being provided with the usual cross handle 30. Adjacent its upper end the post carries an enlarged switch box 3| which includes the fuses, etc., as is customary.

A hand lever 32 is pivotally mounted at 33 intermediate its ends on one side of the switch box 3|. One end of the lever is formed as a handle 34, while the other end of the lever connects with one end of a depending and pivoted link 35 whose lower endis connected with van arm 36 mounted rigid with and projecting rearing position is had by reason of wardly from the housing. The lever 32 cooperates with a quadrant 31 and is provided with a spring actuated manually releasable catch member 38 which engages in a notch 39 in the quadrant when the lever handle 34 is raised and link 35 lowered as far as possible.

Ahead of the caster wheel .unit and at a point below the rear end of the top plate I, the bar 26 carries an offset and somewhat lowered spring seat 40 on which rests a vertical, heavy duty compression spring 4|. The upper end of the spring is capped as at 42, and an adjustment screw 43 extends through the top plate 2 and engages at its lower end on said cap.

Operation Aswill be apparent, the wheels 23 and wheel 28 rest on the floor at all times, and adjustment of the sanding drum to and from a floor engagthe fact that the housing, including side plates 1 which carry said drum, may pivot about stub shafts 20 as an axis. When the lever 32 is raised to a position with the catch member. 38 engaged in notch 39, link 35 has been depressed, forcing the rear ,end

of the housing downward against the compression of spring 4,! and raising the sanding drum from engagement with the floor in the manner shown in Fig. 2.

When it is desired to lower the sanding drum into engagement with the floor, the lever 32 is released and the rear end of the housing is then raised under the influence of compression spring M resulting in the forward end of the housing being lowered and the sanding drum brought into floor engagement. The desired pressure of the sanding drum on the floor may be adjusted or varied by means of adjustment screw 43; the screw being lowered when it is desired to increase the drum pressure on the floor. It will be noted spondingly lowered, which 1 which is also its center of that by reason of the use of the sloping motorbase supporting plate 2, the motor may be kept quite low without interfering with the sanding The centerof gravity of the machine is thus correaids in the ease of operation of the machine. It will also be noted that the motor is disposed so that its axisweight-is nearly in line with but slightly to the rear of the common pivot point or axis of the frame and front wheels. As a'result, the weight of the sanding drum at the front end of the machine is practically balanced by the offset weight portion of the motor disposed rearwardly of said axis, and the frame I on which the motor and sanding drum are mounted thus requires but little spring pressure to lower the drum to the floor, and but little manual force (applied at lever 32) to lift the drum. Also, by reason of the fact that this pivotal axis is also the axis of the front wheels, practically all the greatest weight feature of the machine (the motor) is centered over these wheels. The machine is thus exceptionally easy to steer, since pressure on the rear caster wheel is thus held to a minimum.

The pivotal movement of the housing above described is accomplished without any effect whatsoever on the post 29 and its supported handle 30 as such post is fixed on and is rigid with bar 26 and therefore the handle remains at all times at proper level for the operator. Likewise, as the post 29 is rigid with the bar 26, the sander'can be readily controlled in its direction of movementfor the obvious reason that the supporting wheels for the device and including caster unit 2'! are mounted in connection with said bar. As will be seen from Fig. 3, the bar 26 is deflected laterally intermediate its ends away from the fan housing. This allows the bar to clear the housing while maintaining the rear caster wheel in centered relation to the front wheel, so that the load is evenly-sustained.

From the foregoing'description it will be readily seen that I have produced such a device as substantially fulfills, the objects of the invention as set forth herein. 1

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the 'ap'pended'claims. I

Having thus described my invention, what I claimjas new and useful and desire to secure by Letters Patent is:

.1. In a power driven floor sander, a truck including frontand rear. wheels, spindles for the front wheels journaledin the truck and projecting laterally out beyond said wheels, a frame having side plates through which the outer ends of the spindles project, one spindle being secured in the adjacent side plate and the other spindle having a reduced portion starting at and project ing through avertical slot in the corresponding side plate, a washer on the reduced portion outwardly of the plate, a nut on said reduced portion to engage thewasher and draw up and clamp the spindle against the plate, and an adjustable screw mounted on the frame axially of-the slot and engaging the washer from above.

2. A power sander comprising a wheel mounted truck, a frame, relatively-low pivot mounting means between the frame and truck 'whereby'the frame may rock in a vertical plane, means to control the rocking of the frame, a rotary sanding member mounted on the frame ahead of the truck, a motor for driving the member, and a supporting base forthe motor provided on the frame rearwardly of the member and disposed with an upward slope toward the rear; said base being positioned with, its forward end-below the to rock the frame in a direction to lift the member, a vertical compression spring under the frame adjacent its rear end, a seat on the bar supporting the. lower end of the spring and a vertically adjustable screw supporting the upper end of the spring, mounted in and projecting above the frame for operation.

THOMAS EDWARD LA SALLE. 

